Clover mites, or Bryobia praetiosa Koch, are relatives of ticks and spiders. Clover mites are easily recognizable because they are reddish-green and have long front legs. Thousands can appear in the fall or spring, and they obtain nutrients by sucking on plants to draw out juices. The mites usually prefer grasses and clovers but also eat shrubs and trees. Chemical applications can control clover mite infestations. In many cases, however, you'll have to apply the chemical twice to get rid of clover mites on outdoor plants.
Fill a large shaker bottle with a powder form of boric acid. Take care not to spill the acid outside the bottle or get any on your skin. Do not get the powder acid or bottle wet.
Hold the shaker bottle over the infected outside plants. Shake the dry boric acid directly on top of the clover mites. Make sure it is a windless and dry day or the powder will fly all over. Get the boric acid on as many clover mites as you can.
Wait for three days and inspect the outside plants. If there are still a lot of adult clover mites on the plants, then you know the boric acid did not work. If most of the infestation is gone or only new mites seem to be present on the plants, reapply the boric acid.
Use a bug spray containing malathion if the boric acid powder is not successful. Wear a face mask and gloves as protection and apply the spray according to the label's instructions.
Reapply the bug spray three days later to kill newly hatched clover mites. Wait one week and inspect the plants. If there are still clover mites, spray the plants with malathion once again.